Calculating machine



Filed Feb. 13, 1932 INVENTOR Patented Sept. 20, 1932 UNITED STATES PATENT OFFICE EDWIN F. I3RI'JFJEEIiI', JR, OF MAPLEWOOD, NEW JERSEY, ASSIGNOB, TO MONROE OALOU- LATING- MACHINE COMPANY,'OF ORANGE, NEW JERSEY, A CORPORATION OF DELA- WARE CALCULATING macnnm Application filed February 13, 1932. Serial No. 592,696.

The invention has relation to calculating machines, and more particularly to means for preventing operation of an electricall driven machine while any of the digit selectmg keys 'are in partially set position.

Fig. 2 is a detail plan view of the circuit breaker.

In the drawing the invention is shown as applied to a calculating machine having electrically driven operating means of the type shown in Patent-1,837,785,.issued December 22, 1931 to Fred Masch, and entitled Switch mechanism for calculating machines. The

digit selecting mechanism illustrated is in accordance with the disclosure of Patent 1,399,652, issued December 6, 1921 to E. E.

Phinney and entitled Setting up means for calculating machines.

It will be obvious that the invention may be applied equally well to electric drive means and selector mechanism of widely varying types.

In the drawing, numeral 18 designates the digit determining keys, operable through a the selector bails 19 to set up values, to be registered upon subsequent operation of the machine in the well-known manner. Any desired number of columns of keys 18 may be provided each column having a related lock bar 6, whereby any key depressed in a given column may be locked in set position. As each key is depressed the related lock bar 6 will bemoved laterally by cam tooth of th'e'key, this movement being transmitted to a slide 86, disposed transversely of the locking bars 6 and rovided with a lug 87 engaging a lever 88 orming part of a circuit breaker interposed in the circuit of the motor 100 which drives the operating mechanism of the machine. 'This circuit breaker includes normally engaged contacts 89 mounted upon the ends of spring arms 90, with one of which arms insulated roller 91 contacts, this roller being carried on the free end of lever 88. A spring 92 is fast to lever 88 and serves to hold the parts yieldably in normal position It will be obvious that upon movement of any key 18 from or to set position, lever 88 will be displaced, and the contacts 89 separated, so that the motor 100 cannot be operated until the key arrives in depressed or in elevated position. Therefore, it will not be possible to start the machine before completing the setting of such keys ashave been touched by the operator or before depressed keys, having been released by any Well known clearing means, have returned to inactive position.

It may be noted that the keyboard illustrated is of the flexible type wherein the depression of a key automatically releases any previously depressed key in the same column, and that the present invention prevents operation of the machine until both such keys reach their readjusted positions.

I claim: I v

1. In a calculating machine having settable digit determining keys and operating means including an electric motor; a circuit breaker in the motor circuit havin normally closed contacts, and means opera le by said digit keys and acting toseparate the contacts of the circuit breaker while a key is in partially set position.

2. In a calculating machine having settable digit determining keys and operatin means including an electric motor; a circuit reaker in the motor circuit having normally closed spring contacts, and a lever, displaced by the keys in moving to or from set position and operable to move one of said contacts, to break the circuit. I

3. In a calculatin machine having a plu-' rality of columns 0 settable digit keys and operating means including an electric motor; a circuit breaker in the motor circuit having normally closed contacts, bars each movable by any key of a column during movement 5 thereof to or from set position, and a device, common to said bars and movable thereby to separate the contacts of the circuit breaker.

Si ed at Orange, in the county of Essex and tate of New Jersey, this 11th day of 10 February A. D. 1932.

EDWIN F. BRITTEN, JR. 

